Giovanni Colonna (died 1245)
Giovanni Colonna was a cardinal of the Roman Catholic Church from the Roman noble family of Colonna. He is occasionally named "the Younger" to distinguish him from his near-contemporary cardinal Giovanni di San Paolo, who is frequently considered as related to the Colonna family. As papal legate, he accompanied the Latin Emperor Peter II of Courtenay to Greece, where he was taken captive by Theodore Komnenos Doukas. Released from captivity, Colonna served in 1220–21 as regent of the Latin Empire before returning to Italy in 1223. Colonna participated in the conclaves of 1216, 1227, and 1241–43.